Firstly, pickle your radishes and carrots.
Julienne your carrots and thinly slice your radishes--having a mandolin helps.
Put the julienned carrots and sliced radishes in your pickling liquid and let it sit for 20-minutes to an hour.
Next, cut steak into strips and then marinade (mix all marinade ingredients together in a bowl) for at least 30-minutes.
Warm 2 tbsp of olive oil in a cast iron skillet and then add vegetables (bell peppers and onion). Add pinch of salt and saute at medium to high heat until browned (about 5-7 minutes).
To make the gochujang sauce, add all ingredients to a medium pot, or bowl, and whisk until smooth.
Bring mixture to a boil in a pot and reduce to desired thickness. Add water to make sauce thinner.
To prepare the steak, bring your cast iron skillet to a medium to high heat and add the steak for 6-7 minutes (6-7 minutes per batch, if skillet is small). Set aside when done.
Warm a dry pan to medium-high heat and add corn tortillas in for 15-30 seconds per side.
Now you can assemble your tacos! I like putting the chopped cabbage in first, the bell peppers and onion mixture, Asian pears, beef, picked radishes and carrots and finally top with cotija cheese and green onions. Enjoy!